2009-06-04 05:13:35     LCD driver

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2009-06-04 05:13:35     LCD driver

Nikolay Chokoev (IRELAND)

Message: 75200   

 

Hi,

 

I'm trying to write a LCD driver. It's working except the image is blinking with about 5-10Hz rate (visible). All signals to the LCD seems to be fine (VSYNC, HSYNC, PCLK, etc.). The framerate is 30fps.

 

What I'm wondering is could that behavior to come from the framebuffer? i.e. the image data on the framebuffer to be 'blinking'.

Regards,

Nikolay

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2009-06-04 05:42:22     LCD driver

Michael Hennerich (GERMANY)

Message: 75204    While the display blinks - can you do a

 

#cat /proc/interrupts

 

And post the output?

-Michael

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2009-06-04 07:27:15     Re: LCD driver

Nikolay Chokoev (IRELAND)

Message: 75208   

 

Hi Michael,

 

That's the output:

 

root:/> cat /proc/interrupts

  6:      53938      CORE  Blackfin Core Timer

13:       3225      INTN  PPI ERROR

27:          0      INTN  i2c-bfin-twi

29:          0      INTN  BFIN_UART_RX

30:         61      INTN  BFIN_UART_TX

NMI:          0      CORE  Non Maskable Interrupt

Err:          0

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2009-06-04 07:35:47     Re: LCD driver

Michael Hennerich (GERMANY)

Message: 75209    The blinking is caused by the PPI ERROR interrupt.

 

13:       3225      INTN  PPI ERROR

 

You either failed to program PPI/DMA the right way - or you hit issues detailed here under Troubleshooting.

 

Read this:

https://docs.blackfin.uclinux.org/doku.php?id=ppi

 

-Michael

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